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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_typetraits.examples.destruct"></a><a class="link" href="destruct.html" title="An Example that Omits Destructor Calls For Types with Trivial Destructors">An Example that Omits
      Destructor Calls For Types with Trivial Destructors</a>
</h3></div></div></div>
<p>
        Demonstrates a simple algorithm that uses <code class="computeroutput"><span class="identifier">__has_trivial_destruct</span></code>
        to determine whether to destructors need to be called (see <a href="../../../../examples/trivial_destructor_example.cpp" target="_top">trivial_destructor_example.cpp</a>):
      </p>
<pre class="programlisting"><span class="comment">//</span>
<span class="comment">// algorithm destroy_array:</span>
<span class="comment">// The reverse of std::unitialized_copy, takes a block of</span>
<span class="comment">// initialized memory and calls destructors on all objects therein.</span>
<span class="comment">//</span>

<span class="keyword">namespace</span> <span class="identifier">detail</span><span class="special">{</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">void</span> <span class="identifier">do_destroy_array</span><span class="special">(</span><span class="identifier">T</span><span class="special">*</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">last</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><a class="link" href="../reference/integral_constant.html" title="integral_constant">false_type</a><span class="special">&amp;)</span>
<span class="special">{</span>
   <span class="keyword">while</span><span class="special">(</span><span class="identifier">first</span> <span class="special">!=</span> <span class="identifier">last</span><span class="special">)</span>
   <span class="special">{</span>
      <span class="identifier">first</span><span class="special">-&gt;~</span><span class="identifier">T</span><span class="special">();</span>
      <span class="special">++</span><span class="identifier">first</span><span class="special">;</span>
   <span class="special">}</span>
<span class="special">}</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">inline</span> <span class="keyword">void</span> <span class="identifier">do_destroy_array</span><span class="special">(</span><span class="identifier">T</span><span class="special">*</span> <span class="identifier">first</span><span class="special">,</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">last</span><span class="special">,</span> <span class="keyword">const</span> <span class="identifier">boost</span><span class="special">::</span><a class="link" href="../reference/integral_constant.html" title="integral_constant">true_type</a><span class="special">&amp;)</span>
<span class="special">{</span>
<span class="special">}</span>

<span class="special">}</span> <span class="comment">// namespace detail</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
<span class="keyword">inline</span> <span class="keyword">void</span> <span class="identifier">destroy_array</span><span class="special">(</span><span class="identifier">T</span><span class="special">*</span> <span class="identifier">p1</span><span class="special">,</span> <span class="identifier">T</span><span class="special">*</span> <span class="identifier">p2</span><span class="special">)</span>
<span class="special">{</span>
   <span class="identifier">detail</span><span class="special">::</span><span class="identifier">do_destroy_array</span><span class="special">(</span><span class="identifier">p1</span><span class="special">,</span> <span class="identifier">p2</span><span class="special">,</span> <span class="special">::</span><span class="identifier">boost</span><span class="special">::</span><a class="link" href="../reference/has_trivial_destructor.html" title="has_trivial_destructor">has_trivial_destructor</a><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;());</span>
<span class="special">}</span>
</pre>
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